Elevator door lock



- Ap 1939. w. MAHLKE ELEVATOR noon LOCK Filed Dec. 30, 195'? 2 Sheets-Sheet l w. MA HLKE ELEVATOR DOOR LOCK April 11 1939.

FiledDecgSO, 195'? 2Sheets$heet 2 Wilhelm Patented Apr. 11, 1939 UNITED "STATES PATENT OF FlCE I 2.15am: GK

Application Dccember so, 1937, Serial No. 182,386

, In Austria June 12, 1937 3 Claims. (01. 187-31) This invention relates to a mechanical noiseless elevator door lock which,.in contrast to the hitherto known and used mechanical elevator locks, ensures permanent mechanical locking of the elevator doors throughout the entire ascent and descent, without interruption as the elevator .passes the'individual floors, so that truly noiseless operation is secured.

i The essence of the invention consists in prol vlding, betweenthe bolt, the opening pusher, the

. drawings, in which:

Fig. 1 is a side elevation of the knob housing. Fig. 2 is a front elevation of the knob housing, partly in section.

with the cover and insulating plates removed.

Fig. 4 is a side elevation of the lock housing. Fig. 5 is a section on the line E-F in Fig. 3. Fig. 6 isa section taken on the line 6-1! in Fla. 3.

a horizontal section taken on the line Fig. 2. r

a similar 'sectiontaken on the line f m. 'A--Bi,l11"18.3.-.v

Figs; 9f'and,"i i l-are sections taken. on the line 35 CD in'Figll and Fig; 3, respectively.

Fig. 1118; section taken on the line 'I-K in Fig. 5, and i Fig. 12 is a section taken on the line L-M in Fig. 6.

40 In the form of construction shown in the drawings in the bolt movably mounted in the lock housing thereis pivotally mounted at its upper end, about apin m, a lever h (Figs. 2 land 3). Against this lever 72. there acts the locking spring 4 f with the aid of the intermediate piece e, with the result that the roller 0 mounted for rotation about the pin n at the lower end of the lever is held clear of the unlocking ledge 1 (Figs. 3 and 8). On operation of the knob 11 the'thrust member (1 50 (Fig. 2) supported in the knob housing presses against the opening pusher or slide .1 which is guided in the lock housing, and whichacts uponv the lever h. As long as the elevator is in an intermediate position between two consecutive floors 55 operation of the knob a has the effect of moving "Fig. 3 is a front elevation of the lock housing is the lever 11 against the action of the spring I towardsthe right, without thereby causing the bolt r to move. As soon as the elevator reaches a floor where an unlocking ledge I (Fig. 8) .is; provided operation 01' the knob 11 causes the lever 6 h to be moved about the pivot m until the roller 0 strikes against the ledge l, whereupon there takes place further pivotal movement about this point of contact as a fulcrum, with the result that the bolt 1' is brought out of engagement with its aperture 0 in the door (Figs. 2 and 3). The door is thus unlocked and can be opened.

. Fig. 5 shows how, simultaneously with the re-' traction of the bolt 1', there is eflected an interruption of the control current circuit. With the 15 interposition of insulating plates p there are secured to the bolt r vertical rails t on which the contact bridge is is vertically slidabie. The contact bridge k is horizontally guided by means of the guide q which is coupled to a block a guided in a vertical slot in the lock housing (see Figs.

3 and 11). On retraction of the bolt r the contact bridge is is carried along by the rails t-with the result that the contacts i are separated.

Interruption at the contacts i is also efiected when the door is opened, with the aid of the sliding block 9 (Figs. 3, 5, and 11) and of the inclined track b (Fig. 1) provided in the knob housing. The sliding block o engages in this inclined trackway b, so that on opening of the door a downward movement of the sliding block is brought about.

In its downward movement thesliding block 9 takes the guide or and the contact bridge k along with it, the latter being likewise forced downwards along the rails t, with the result that the contacts i-are further separated. This positively eiiected double interruption of the current circuit controlling the elevator ensures absolutely reliable functioning.

With the aid of the sliding block 0, which is furnished with a locking catch v, the bolt r may be retained in its open position, since owing to the downward movement 'of the sliding block y elfected on opening of the door the catch 0 comes into position in front of the bolt 1'.

On closing of the door there is eilfected' by the trackway b (Fig. 1), in the reversed order, first of all lifting of the sliding block g Figs. 3-5 and Fig. 11), whereby the bolt r is released, and, owing to the greater component of the force of the locking spring f- (Fig. 3), which acts through the intermediary of the nose e against the lever 71.,

thrusting forward of the bolt 1- into its aperture 0 (Figs. 2 and 3). Owing to the fact that the point of application of the force of the spring I to the 'lever h has been moved nearer-towards its point of support in the bolt r than towards the point of application of the opening pusher or slide 3 the greater component of the springs force acts first upon the bolt r and brings about the shifting thereof, after which the lesser component of the force of this spring brings about forward movement of the slide s against its recess in the lock housing. In the end position shown in Fig. 3 the roller is again retracted clear of the unlocking ledge l, and noiseless operating thus ensured. On the upward movement of the slidingblock a the contacts 1 are closed by the contact bridge k in a vertical direction, and also in a horizontal direction by the thrusting forward of the bolt 1', through the intermediary of the insulating plate 1) and the rails t.

Owing to the upward displacement of the point of application of the spring 1 to the lever h (Fig. 3) the result of operating the door knob a between two floors or stopping points of the elevator is to press the bolt r with certainty into its aperture, since the force acting thereon is greater than the component of force acting upon the opening slide 8. It is therefore impossible for the bolt r to be retracted by operation of the door knob or opener between any two stopping points,

since in the absence of the unlocking ledge the lever h can merely be oscillated. The lock according to the invention thus enables keyless door latches to be used on elevators without risk and without infringing legal regulations. a

tion with -said cam surface, a spring acting on said swing lever adjacent the pivoted end thereof to normally hold said bolt in said projected position and said follower element out of contact with said cam surface and an opened slide having one end projecting from said frame casing and the other end disposed for action on said lever intermediate said follower element and spring in a direction opposite to that of the force exerted by the latter, said door casing comprising a handle and a 'reciprocable thrust member controlled by said handle and adapted to actuate said opener slide in the frame casing in closed position of the door.

2. An elevator door look, as claimed in claim 1, in which the frame casing comprises further a guide block projecting in closed position of the door into an inclined guide groove provided in the door casing so as to be lowered and raised upon opening and closing, respectively, of the door, and a catch secured to said guide block inside of the frame casing, said catch projecting into the path of said slide bolt and securing the same in its retracted position while the door is open.

3. An elevator door lock, as claimed in claim 1,

in which the frame casing comprises further contactsfor the supply of current to the hoisting mechanism'of the elevator, a movable contact bridge for said contacts, a vertical guide rail secured to said slidable bolt, said contact bridge being connected to said guide rail .to be free for vertical movements only relative to the latter and a guide block projecting in closed position of the door into an inclined guide groove in the door casing so as to be lowered and raised upon opening and closing, respectively, of the door, said contact bridge being connected to said guide block to be free for horizontal movements only relative to the latter, whereby said contact bridge is moved horizontally relative to said contacts upon displacements of said bolt and vertically of said contacts upon opening and closing of'the door.

WILHELM MAHLKE. 

